— 401 — 
characterized by the accession of forms of Pecopterids, (1) Taeniop- 
teris, Cycads and Ginkgoales. 
Further proof of climatic amelioration during early Gondwana 
time is offered by the fossil woods. Those described by Shirley (2) 
and Arber (3) from the lower portion of the series in New South Wa- 
les are all characterized by well marked and thick annual rings. 
Also I am at liberty to add here that Dr. Derby has obtained, in 
Sdo Paulo, apparently from horizons lower than those from which 
the woods examined by myself were derived, fossil gymnospermic 
types in which the rings areclearly in evidence though not broad. 
On the other hand, in the woods collected in the interval extending 
100 meters above the Iraty black shale there is little or no evidence 
of annual rings, as may be noted by reference to Plates xiii and xiv 
of this report. The modified clmate shown to prevail in the region 
of the Iraty black shale should have been well suited to the introdu- 
ction of some of the associates of Psaronius; and, as I have already 
remarked, it is probable that the paleobotanical study of this part of 
the series will lead to thediscovery of other migrants from the cos- 
‘mopulitan flora. 
In passing it may be of interest to mention that the fossil wood 
from beds regarded as Triassic near Santa Maria station in Rio Gran- 
de do Sul, appears to exhibit very narrow, and rather poorly defined 
annual rings. 
From the above review of thedatait seems probable that the coal 
measures in the states of Santa Crtharina and Rio Grande do Sul 
areof Permian age; that aportion at least of the basal boulder beds 
of the Brazilian coalfields are approximately contemporaneous with 
glacial activity and the deposition of morainic material in certain 
other regions of a great southern continental area, or approximate 
areas, called «Gondwana-leand»; that tha beds next above, containing 
a pure Gangamopteris, or older Gondwana flora, were laid down 
during a period of waning cold climate following the period of glacia- 
tion; and that with ameloration of climatic conditions other types, 
including identical speciesin the Northern cosmopolitan flora, were 
(1) The earlicr forms described as Cladophlebis and Pccopterts {rom the Palaeozoioc 
Gondwanas are very intimately connected with the forms lrom the Permian of the Eas- 
tern United States described by Professor Fontaine and Doctor White as Callipter7- 
dium. 
(2) Bull. Geol. Surv. Queensland, no. 7, 1898, p. I. 
(3) The Glossopteris flora, 1905, p, 191. 
